The 25-year-old first baseman had a flare-up in his back in late August and an MRI last week revealed a lower back-strain that the doctor said would best treated if he sat out from all baseball activities for the next 10 days, according to the report. Yesterday, he resumed those activities with some light hitting, infielding and running.

Rizzo said the best case scenario is that he's back in the lineup for the tail-end of Chicago's away series vs. the Pirates this weekend -- encouraging news since it had been reported last week that he may be shut down for the season.

He is hitting .278 with 30 homers and 71 RBI. The Cubs were fifth in the NL Central heading into Tuesday night's game in Toronto against the Blue Jays.

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